Synthesis of two 6-s-cis locked stereoisomeric analogues of the steroid hormone 1α,25-dihydroxyvitamin D3: 1α,25-dihydroxy-19-nor-previtamin D3 and 1β,25-dihydroxy-19-nor-previtamin D3
作者:Mónica Dı́az、Miguel Ferrero、Susana Fernández、Vicente Gotor
DOI:10.1016/s0040-4039(99)02152-8
日期:2000.1
An efficient synthesis of A-ring precursors 8 and 9 from inexpensive commercially available (−)-quinic acid has been developed. A-Ring synthon 8 has been obtained through a short sequence (eight steps) in high overall yield (30%). One key step in the synthesis of A-ring precursor 9 is the selective deprotection of a silyl ether in an α,β-unsaturated ester 12. However, of note is the excellent yield
已经开发了由廉价的可商购获得的(-)-奎尼酸有效合成A-环前体8和9的方法。通过短序列(八步)以高总产率(30%)获得了A-环合成子8。合成A环前体9的一个关键步骤是在α,β-不饱和酯12中对甲硅烷基醚进行选择性脱保护。但是,值得注意的是,Mitsunobu方法在衍生物15上的收率很高,这与构型的全部转化有关,生成了酯16。A环合成子8和9与适当的CD环/侧链片段的偶联7,提供了访问6-小号-顺式锁定类固醇激素1α的类似物,25-(OH)2 -D 3:1α,25-(OH)2 -19-也不-pre-d 3(3)的和新颖的1β,25-(OH)2 -19-或-pre-D 3(4)。